A woman tells the nurse that her 6-year-old daughter has severe nosebleeds. Which of the following instructions should the nurse give this woman to manage nosebleeds

A. Help the child assume a comfortable position with her head tilted backward.
B. Tilt the child’s head backward and place firm pressure on the nose.
C. Help the child lie on her stomach and collect the blood on a clean towel.
D. Place the child in a sitting position with her neck bent forward and apply firm pressure on the nasal septum.

要了解某批灯泡的平均寿命，宜采用的调查方法应为（）。

A.重点调查

B.抽样调查

C.直接调查

D.全面调查